Three-dimensional Virtual Terrain Synthesis Guided By The Contour Lines Of The Mountain Image

With the development of intelligent information technology,virtual reality technology will become a new model of education and teaching in the future.In order to generate a digital environment that is highly similar to the real outdoor environment for obtaining the strongly realistic experience,it is inseparable from the photorealistic rendering of 3D virtual terrain.Therefore,3D terrain synthesis has become a hot spot in the field of virtual reality.In this paper,we focus on the topic of 3D terrain synthesis technology and propose a 3D terrain synthesis algorithm guided by outlines of mountain image.Our main works include mountain outlines extraction,global feature sketch construction,initial terrain synthesis and elevation matching as follows:1.The edge detection technology is used to detect the outlines of the image,and the independent outline of mountain is obtained through the outline splitting operation.2.After obtaining independent outlines of the mountain,we predict the depth information of each mountain outline by the deep of convolution neural network model.Then according to the predicted depth information,the following optimization process is executed on the outline:outline depth fitting,outline depth ranking,outline spacing adjustment and outline complementation.Finally,we reconstruct the outline by using the depth information of the fitted outline,the occlusion relationship between the outlines and the image imaging principle.The reconstructed outline is a global feature sketch that controls the synthesis of the 3D terrain.3.In order to make the synthesized 3D terrain more realistic,under the control of the global feature sketch,our algorithm takes the terrain block with the local detail as the basic element,synthesizes the initial 3D terrain by the terrain block matching,filling and blending.4.Due to the differences in the local detail between the terrain blocks and the outlines,the synthesized initial terrain and the mountain outline do not match on the elevation.Therefore,we take the outline as the constraint condition to analyze the synthesized initial 3D terrain through the elevation matching process;the final generated 3D terrain is matched with the outline.On the basis of the theoretical study of the algorithm above,we realize the 3D terrain synthesis guided by the outline of the mountain image.The experimental results show that our algorithm can synthesize desired 3D terrain under the constraints of real outline of mountains.